The Echinoid Directory

Togocyamus Oppenheim, 1915, p. 20

Diagnostic Features
  • Small, lentil-shaped test (less than 5 mm in length) with rounded ambitus
  • Apical disc central with four gonopores. Three or four hydropores at most
  • Petals distinct, narrow; plating simple. Slightly bowed. Pore-pairs following plate sutures
  • Ambulacral pores arranged as a uniserial line along adradial suture, two or three to a plate at the ambitus
  • Interambulacral zones wider than ambulacral zones
  • Peristome central and somewhat sunken
  • No food grooves
  • Periproct opening on aboral surface
  • Interambulacral zones continuous
  • Single open sphaeridial pit at centre of each ambulacrum
  • 10 radial internal partitions
Distribution
Late Palaeocene, West Africa and Nigeria
Name gender masculine
Type
Echinocyamus (Togocyamus) seefriedi Oppenheim, 1915, p. 10-13, by original designation
Species Included
  • T. seefriedi Oppenheim, 1915; Late Palaeocene, Nigeria, Senegal, Togo
  • T. alloiteaui Roman & Gordinski 1959: Late Palaeocene, Senegal
Classification and/or Status
Clypeasteroida, late stem group member
Remarks

Differs from crown group Clypeasteroida in having open sphaeridial pits and in having pores below the petals confined to vertical bands that follow the adradial sutures.

Kier, P. M. 1982. Rapid evolution in echinoids. Palaeontology 25, 1-9.

Oppenheim, P. 1915. Beitrage geol. Erforsch. Deutsch. Schutzgeb., 12, p. 20.

Roman, J. & A. Gorodiski 1959. Echinides Eocenes du Senegal. Notes du Service de Geologie et de Prospection Miniere, Dakar 3, 1-91.